Schottky diodes are well suited for use in high frequency applications because they have short reverse recovery times and low forward voltages, i.e., low losses. However, they have breakdown voltages of less than 200 volts which limits their use to low voltage applications. Schottky diodes are typically comprised of a high work function metal in contact with an N-type conductivity epitaxial layer which is grown on a substrate material of N-type conductivity. Techniques for increasing the breakdown voltage have included increasing the thickness of the epitaxial layer, increasing the resistance of the epitaxial layer, and forming a guard ring in the epitaxial layer. A drawback with these techniques is that they also increase the forward voltage and decrease the switching speed of the Schottky diode.
Accordingly, it would be advantageous to have a Schottky diode capable of withstanding a large reverse bias voltage while having a low forward voltage drop and fast switching characteristics. It would be of further advantage for the method for manufacturing the Schottky diode to be cost and time efficient and compatible with Schottky diode manufacturing processes.